Erosion
The Erosion subnode is available from the context menu (right-click the Wall parent node) or from the Physics toolbar, Attributes menu. Use it to calculate the rate of erosive wear or the total mass removed due to the impact of particles on a boundary.
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When Specify release times is selected from the Particle release specification list in the physics interface Particle Release and Propagation section, the Erosion node calculates the total mass lost per unit area (SI unit: kg/m2).
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If Specify mass flow rate is selected from the Particle release specification list, the Erosion node calculates the rate of erosive wear (SI unit: kg/m2/s).
Erosion Model
Select an Erosion model: Expression, Finnie (default), E/CRC, Oka, or DNV. Then enter the following settings:
Expression
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If Specify release times is selected from the Particle release specification list in the physics interface Particle Release and Propagation section, enter the Mass removed by particle Δmi (SI unit: kg). The default is 10-15 kg.
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If Specify release times is selected from the Particle release specification list, enter the Erosive wear of particle EM,i (SI unit: kg/s). The default is 10-15 kg/s.
Finnie
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Fraction of particles cutting in an idealized manner ci (dimensionless). The default is 0.1.
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Ratio of normal and tangential forces K (dimensionless). The default is 2.
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Surface hardness HV (SI unit: N/m). The default is 2 GPa.
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Mass density of surface ρ (SI unit: kg/m3). The default is 7,500 kg/m3.
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Moment of inertia calculation. The default is Isotropic sphere. If User defined is selected, enter an expression for the Particle moment of inertia Ip (SI unit: kg m2).
E/CRC
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E/CRC model coefficient C (dimensionless). The default is 2.17 × 10-7.
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Brinell hardness of surface material BH (dimensionless). The default is 200.
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Particle shape coefficient Fs (dimensionless). The default is 0.2.
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E/CRC model exponent n (dimensionless). The default is 2.41.
Oka
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Oka model coefficient K (SI unit: m3/kg). The default is 65 mm3/kg.
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Reference diameter dref (SI unit: m). The default is 326 μm.
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Reference velocity vref (SI unit: m/s). The default is 104 m/s.
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Each of the following dimensionless Oka model coefficients:
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k1 (default is −0.12) and k3 (default is 0.19).
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q1 default is 0.14) and q2 (default is −0.94).
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s1 (default is 0.71) and s2 (default is 2.4).
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Surface hardness HV (SI unit: N/m2). The default is 2 GPa.
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Mass density of surface ρ (SI unit: kg/m3). The default is 7,500 kg/m3.
DNV
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DNV model coefficient K (dimensionless). The default is 2 × 10-9.
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DNV mode exponent n (dimensionless). The default is 2.6.
If Specify release times is selected from the Particle release specification list in the physics interface Particle Release and Propagation section, it is possible to multiply the eroded mass by another scale factor. Select an option from the Number multiplication factor specification list: From physics (the default) or User defined.
For From physics the extra scale factor is usually equal to 1. However, if the Enable macroparticles check box is selected in the physics interface Additional Variables section, the scale factor is instead taken from the built-in auxiliary dependent variable for the particle number multiplication factor, which can be initialized in the Settings windows for most particle release features.
For User defined, specify the extra scale factor directly. Enter a value or expression for the Number multiplication factor nn (dimensionless). The default is 1.
Smoothing
By default the Compute smoothed accumulated variable check box is cleared. Select this check box to define smoothed accumulated variables for the rate of erosive wear or total eroded mass, by taking a local average at each point on the surface. Enter a value or expression for the Smoothing radius r (SI unit: m). The default value is 0.1 m.
Pipe Erosion due to Contaminant Particles: Application Library path Particle_Tracing_Module/Fluid_Flow/pipe_elbow_erosion
Erosion Theory in the theory section.